Animation of One Space Colony

[Atlan0001]

I'm a fan of the Stanford Torus in-space 'city-state' colony 'island Space Ark', but here is a current animation of O'Neill's cylindrical colony 'island Space Ark' you might like to see:

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In space, once we've tooled up to the mining of materials and building its first factory construction shack, constructing megastructures such as the Stanford Torus and the O'Neill 'Island 3' won't be nearly as hard as constructing skyscraper buildings on Earth.

 

[billslugg]

There is a fatal flaw in the proposal. The strength of the outer skin needs to obey the hoop stress equation. The tension in the external member equals internal pressure times the radius. For 6.5 km diameter and 15 psi inside, the skin strength must be 20,000,000 pounds per linear inch. If made of high strength steel (77,000 psi) the skin must be 20 feet thick. Windows of fused quartz would need to be 228 feet thick. Much smaller cylinders are required, no more than about 200 meters in diameter.

 

[Atlan0001]

There is a fatal flaw in the proposal. The strength of the outer skin needs to obey the hoop stress equation. The tension in the external member equals internal pressure times the radius. For 6.5 km diameter and 15 psi inside, the skin strength must be 20,000,000 pounds per linear inch. If made of high strength steel (77,000 psi) the skin must be 20 feet thick. Windows of fused quartz would need to be 228 feet thick. Much smaller cylinders are required, no more than about 200 meters in diameter.

These designs weren't drawn up by the stupid, Bill. They were done by physicists, astrophysicists, and engineering experts in their fields. They've worked on the ideas and plans, and potential problems, for that particular physical environment, so different from our environment, for fifty years now!

As I, myself, have said many times in the past decades, I'm not a fan of any "Islanded Space Ark" city-state colony other than a Stanford Torus spin-gravitied inner tube inside a massive integrated protective outer-tube that does not spin. But an O'Neill double-opposed cylindered Island-3 colony is possible. Megastructures that would be impossible to even think of on Earth are very possible in the physics of the outer-space environment. The amount of mass material thicknesses of the colony shell masses you contemplate and mention as necessary will be no problem whatsoever regarding these colonies, every O'Neill Island-3 double cylinder will have a total shell material mass of a small asteroid, not only for wanted integrity but for wanted protections against much of the unfriendly environment of outer-space.

There will be no immediacy regarding O'Neill Island #3s. It will be tooled up to -- worked up to -- via smaller islanded custom station and colony structures. Though I don't favor it, as I say, I press that when that size is reached, there be no larger structures ever as totally unnecessary. Many should be favored over an increasingly 'Titanic' quality lump. By that time we should be reaching out into the universe looking for many new mainframe worlds like the Earth and Mars . . . who needs a stone coffin-tomb of 'Dyson's Sphere'?

 

[billslugg]

No one is immune from the hoop stress equation. Every engineer who designs pressure vessels is painfully aware of it. If these designers want a 6.5 km diameter shell at 15 psi they are going to have to belly up to the bar and put down 20,000,000 pounds per linear inch of shell strength. No exceptions.

 

[Atlan0001]

No one is immune from the hoop stress equation. Every engineer who designs pressure vessels is painfully aware of it. If these designers want a 6.5 km diameter shell at 15 psi they are going to have to belly up to the bar and put down 20,000,000 pounds per linear inch of shell strength. No exceptions.

I repeat, Bill. Ignorant and stupid professional physicist and engineering idiots are not dealing in these designs! Ignorant and stupid physicist and engineering idiots have not been dealing in the designs and the environment for them for fifty years and more! NASA has the artwork and more for these in-space colonies on their website and I don't really believe they are that stupid with the various backgrounds in space, physics, and engineering they have!

We will design, shape and construct megastructures, and megastructures with all the spin gravity we will want and need, out there if and when we get out there on a permanent basis!

And who knows, we may discover how to do so-called "artificial gravity" just by using quantum effects without needing either large masses or spins, or thrusts. "Who knows! The horse might sing."

 

[billslugg]

You nailed it when you said: "Art". The people who draw the pictures are not the people who design the shell. When confronted with the impossibilities of their designs they will point out these are only "concepts" and not to be taken as final form. Or they will predict that by then we will have materials strong enough. But, right now, we don't have such materials.

 

[Atlan0001]

You nailed it when you said: "Art". The people who draw the pictures are not the people who design the shell. When confronted with the impossibilities of their designs they will point out these are only "concepts" and not to be taken as final form. Or they will predict that by then we will have materials strong enough. But, right now, we don't have such materials.

And don't them to construct initially two pressure-less hollow mega-caves in outer-space. Then begin them rotating for outer-rim gravity. Then begin feeding blisters of breathable atmosphere to the rim, the pressure of which will not be that of the bottom of the Marianna's Trench, but the centripetal point of these caves will be the center point line along the center of these colonies and NOT some point to the other side of a Marianna's Trench. In other words, the centripetal point of vortex, what little vortex there will be, if any, will be distantly over the heads of the people who will occupy the colonies, thinning toward them, and NOT pushing, pressurizing, to underneath their feet.

I say, and have said now, that gravity, even regarding our Earth, doesn't operate to any center point but is the dark energy waving of accelerating expansion in opening system, emergent SPACE always seeking the open system of the universe . . . and in and as its wave wake the strong (nuclear) binding force! The monopole moment of the fundamental electroweak force is the 0-point-portal-singularity always attributed to gravity . . . and centers in the center line of the rotating cylinder colony's cave, as well as the center points of the Stanford Torus colonies.

 

[billslugg]

Spinning the cylinders in order to increase the air pressure only makes the tension on the outer skin worse. There is no escape from the hoop stress equation. The largest practical cylinder would be around 100 meter radius. Current technology could make a strong enough skin, the radius would be large enough to prevent dizziness from the spinning needed to make gravity. A 6 km cylinder is that of an artist unconcerned with practicalities.

 

[Atlan0001]

Spinning the cylinders in order to increase the air pressure only makes the tension on the outer skin worse. There is no escape from the hoop stress equation. The largest practical cylinder would be around 100 meter radius. Current technology could make a strong enough skin, the radius would be large enough to prevent dizziness from the spinning needed to make gravity. A 6 km cylinder is that of an artist unconcerned with practicalities.

Gravity is a spread to the outer rim and the outside of the colony, and so is the pressure spread rather than concentrating. This isn't the Earth we are talking about, Bill, the closed systemic center point of which is a powerful quantum monopolar electroweak point and NOT gravitational . . . regardless of what we've been indoctrinated with for so long.

The outer rim territory, and the colonists in it, will effectively 'orbit' the stretched center electroweak point-line vortex singularity of the colony. Effectively, the colony's "black hole" counterpoint to the outer rim territory's "white hole" spread in accelerating expansion to open system and the frontier universe. But, that "black hole" counterpart 'is' a black hole counterpoint and the only reason for the portal, the wormhole, the JUMP-SPACE, is gravity wave's wake, the strong (nuclear) binding force (aka, too, the asymptotic Casimir force and effect)!

 

[Atlan0001]

Bill, I'm enjoying this line of debate to no end. I once had a close friend, my second closest friend in my long life to my lovely wife of a good deal more than fifty years, and everyone thought when we got to debating things that we were going to kill each other (which couldn't have been further from the truth). I'm going back "liking" your posts because I'm "liking" so much crossing swords, fencing, with you, regarding the above!

 

[Atlan0001]

Seeing again the article on Jeff Bezos' great but unoriginal vision concerning a trillion people living throughout the Solar System:

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A trillion is just a beginning, but by the time it's a trillion we may be traveling the universe to other star systems and worlds thanks to a one in a trillion idea and adjustment from a one in a trillion "nothing" of a spaceship's mechanic.

Barely two-thirds, if even that many (maybe just half if even that many), of the trillions, or quadrillions, of people who will be living out there will be living their lives out in Stanford Torus or O'Neill Colony-3 non-planetary mainframe system colony-Ark city states in space. The rest will be living in specialized, customized, "Voyager Station" or "2001: A Space Odyssey" type space stations, or aboard space Oriental 'Junk' type ship-homes or other ships plying the lanes and the near and far distances of the Solar System (all the way out into interstellar space)!